Article
Environmental Sciences
Linbo Qian, Ying Long, Hangyu Li, Zifei Wei, Cong Liang, Renlan Liu, Mengfang Chen
Summary: In this study, the removal of hexavalent chromium (Cr(VI)) and Trichloroethylene (TCE) by rice straw pyrolysis biochar supported nanoscale zero-valent iron (nZVI) was investigated. The results showed that biochar supported nZVI effectively removed Cr(VI) and TCE in single pollutant system, but mutual inhibition occurred when both contaminants were present. Therefore, the mutual inhibition effect should be evaluated in the remediation of combined contaminated groundwater.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Xiangpeng Tan, Muhammad Shaaban, Jianwei Yang, Yajun Cai, Buyun Wang, Qi-An Peng
Summary: This study used ramie biochar (RBC) to activate nano zero-valent iron (nZVI) for enhanced removal of hexavalent chromium (Cr(VI)). The RBC-nZVI composite showed significantly higher efficiency in Cr(VI) removal compared to RBC or nZVI alone, due to a synergistic effect between RBC600 and nZVI on the reduction reaction of Cr(VI) and increased adsorption sites. This research provides a new approach for utilizing ramie waste and effectively addresses the limitations of nZVI for efficient and rapid Cr(VI) remediation.
Article
Environmental Sciences
Jian Zhang, Xianni Yang, Jun Shi, Mingyue Zhao, Weiqin Yin, Xiaozhi Wang, Shengsen Wang, Changai Zhang
Summary: The study demonstrated that ZVI supported by biochar derived from cellulose, hemicellulose, and their binary mixture showed better Cr(VI) removal capacity. The higher ordered and graphitic carbon structure was responsible for this improved performance, facilitating electron transfer and reduction of Cr(VI).
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Alessio Siciliano, Giulia Maria Curcio, Carlo Limonti
Summary: The study conducted experimental research on the removal of chromium using zero valent magnesium particles in a packed batch column, finding that the process performance was significantly influenced by pH values, and the temperature had a correlation with removal yields depending on pH values. The results provide insights into the potential applications of zero valent magnesium in water and wastewater purification.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Chemistry, Multidisciplinary
Jianwei Yang, Xiangpeng Tan, Muhammad Shaaban, Yajun Cai, Buyun Wang, Qi'an Peng
Summary: BC-nZVI composites are effective in removing Cr(VI) from contaminated soil while increasing microbial diversity and abundance, with no significant adverse effects on soil quality or microorganisms.
Article
Environmental Sciences
Miao Cai, Jian Zeng, Yaozong Chen, Peng He, Fang Chen, Xu Wang, Jinye Liang, Chunyao Gu, Dongli Huang, Ke Zhang, Min Gan, Jianyu Zhu
Summary: In this study, a novel biochar-supported zero-valent iron composite was synthesized and characterized for the removal of Cu(II) and Cr(VI). The composite showed better removal performance compared to single biochar and mineral, with a pH-dependent removal mechanism via heterogeneous multilayer chemisorption. Electrochemical analysis demonstrated higher electrical conductivity and electron transfer rate in the composite, indicating its potential for efficient heavy metal remediation.
Article
Engineering, Environmental
Xin Zhang, Hongxing Xu, Min Xi, Zhixiang Jiang
Summary: Remediation of Cr(VI) pollution by nanoscale zero-valent iron-loaded biochar (nZVI-BC) is a hot research topic. The interaction between natural organic matter (NOM) and Cr(VI) on their adsorption on nZVI-BC was investigated. nZVI-BCs with different ratios of Fe:C were prepared, and the optimal Fe:C ratio was determined to be 3:1. Adsorption experiments showed a strong competitive adsorption between Cr(VI) and NOM. Characterization techniques revealed the mechanisms behind the decreased Cr(VI) reduction and adsorption, as well as the decreased adsorption of NOM.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Environmental Sciences
Jinlan Zhang, Lihong Xie, Qiyan Ma, Yiyang Liu, Jie Li, Zhifeng Li, Shangyi Li, Tingting Zhang
Summary: Ball milling technique was introduced to modify Zero-valent iron biochar composites (ZVI/BC) for the removal of Cr(VI). Results showed that the maximum Langmuir adsorption capacity for Cr(VI) increased 2.08 times after ball milling. The initial adsorption rate also significantly increased. The improved dispersion of ZVI, enhanced contact between ZVI and biochar, and increased oxygen-containing functional groups in biochar contributed to the enhanced removal of Cr(VI).
Article
Green & Sustainable Science & Technology
Min Zhuang, Hui Wang, Lu Qi, Liqiang Cui, Guixiang Quan, Jinlong Yan
Summary: In this study, activated biochar was successfully prepared as a support for sulfidated nanoscale zero-valent iron (S-nZVI@ABC), significantly increasing the specific surface area and achieving even particle dispersion for improved removal efficiency of Cr(VI). Higher S/Fe ratio, dosage, lower pH, and Cr(VI) concentration all contributed to enhanced removal efficiency. The removal process was endothermic and involved multiple interaction mechanisms in the removal of Cr(VI) by S-nZVI@ABC.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Engineering, Environmental
Giulia Maria Curcio, Elvis Gribaldo Aucancela Rivera, Carlo Limonti, Tiziana Andreoli, Rajandrea Sethi, Alessio Siciliano
Summary: This study investigates the reduction of Cr6+ using zero-valent magnesium (ZVM) in a continuous flow system. The research explores the process kinetics under different operating conditions and examines the effects of inlet Cr6+ concentration, pH, and co-existing ions. The results show that ZVM powder exhibits the highest reactivity and can effectively remove Cr6+ even at higher pH levels.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Chemistry, Physical
Ge Gao, Lei Zhang, Yixin Shi, Shengjiong Yang, Gen Wang, Huining Xu, Dahu Ding, Rongzhi Chen, Pengkang Jin, Xiaochang C. Wang
Summary: The study found that the microscopic galvanic cell (mGC) exhibited higher Fe(II) release performance compared to ordinary nanoscale-ZVI (nZVI), resulting in improved Cr(VI) removal efficiency. Density functional theory (DFT) revealed that the close proximity of cathode and anode in mGC enhanced the galvanic corrosion of Fe(0). Additionally, hydroxyl radicals generated by a series of side-reactions slightly hindered the reduction of Cr(VI) in the system.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Engineering, Environmental
Wenying Zhang, Linbo Qian, Lu Han, Lei Yang, Da Ouyang, Ying Long, Zifei Wei, Xinzhu Dong, Cong Liang, Jing Li, Mingyue Gu, Mengfang Chen
Summary: The study successfully demonstrated simultaneous removal of Cr(VI) and TCE from aqueous solutions using AT-nZVI/PS systems, with removal efficiencies reaching over 90% for both contaminants.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Environmental Sciences
Wenxian Chen, Xiangwei Xu, Jinping Cui, Zhenyang Zhou, Yuyuan Yao
Summary: This study developed a novel bifunctional material that can efficiently degrade organic pollutants and eliminate hexavalent chromium. The material exhibited high apparent first-order constant and storage stability, enabling efficient degradation and removal of harmful substances at low temperatures.
Article
Engineering, Environmental
Qi Zhang, Xuezhu Ye, De Chen, Wendan Xiao, Shouping Zhao, Jun Li, Hui Li
Summary: In this study, Fe-rich sludge from swine wastewater was transformed into ZVI biochar composites through pyrolysis, and their effectiveness in removing Cr(VI) from synthetic solutions was evaluated. The results showed that both acidic pH and dissolved oxygen contributed to Cr(VI) removal, and the composites with a core-shell structure exhibited higher removal efficiency. X-ray photoelectron spectroscopy analysis revealed the removal mechanisms of adsorption, micro-electrolysis, and co-precipitation for one composite, and adsorption, reduction, and electrostatic attraction for the other. ZVI biochar composites have the potential to remediate Cr(VI)-contaminated wastewater.
JOURNAL OF WATER PROCESS ENGINEERING
(2022)
Article
Environmental Sciences
Wenying Zhang, Linbo Qian, Yun Chen, Da Ouyang, Lu Han, Xiao Shang, Jing Li, Mingyue Gu, Mengfang Chen
Summary: The attapulgite treated by HCl and HF showed increased silicon content and active silicon sites, leading to higher removal efficiency for Cr(VI). Silicon played a significant role in the reductive precipitation of Cr(VI) through Si-O-Fe coupling.